Behavioral eco-lect2: Decision making under certainty part 3

Loss aversion

Standard economic prediction of a loss

So, the standard economic model predicts that gains and losses are the same

However, it turns out that often people value losses larger than a similar gain.

Utility loss of going from 1 to 0 units:
U(1) – U(0)

The ‘reference point’ plays an important role

Utility gain of going from 0 to 1 units:
U(1) – U(0)

see graph slide 21/33

Endowment effect: A circumstance in which an individual values something which they already own more than something in case they do not yet own it.

Example of the endowment effect slide 23/33

Willingness to accept (WTA)

Willingness to Pay (WTP)

the gap between WTA and WTP => an endowment effect

One explanation: loss aversion (=being afraid of losses)

Value function: To describe the endowment effect, economists use the ‘value function’

It is measured in changes:


Important: the reference point (do you start from 0, or from 1, or from a loss?)

The side of losses is steeper than the side of gains.

graph slide 25/33

Application of the value function

The reference point is important. It allows to model that you are ‘disappointed’ or ‘surprised’ by something with the same end effect.

see example 26/33

graph 27/33